Tracker-bar.



P. H. HARTZELL.

TRACKER BAR.

APPLICATION FILED JAN. 2, 1913.

Patented Mar. 9, 1915.

UNITED STATES PATENT OFFICE.

FOREST H. HARTZELII, 0F DAYTON, OHIO, ASSIGNOR TO THE CROWN MANUFACTURING- COMPANY, OF DAYTON, OHIO, A CORPORATION OF OHIO.

TRACKER-BAR.

Application filed January 2, 1913.

To all whom it may concern:

Be it known that I, F onns'r H. Human, a citizen of the United States, residing at Dayton, in the county of Montgomery and State of Ohio, have invented certain new and useful Improvements in Tracker-Bars, of which the following is a specification.

My invention relates to mechanically operated musical apparatus, and particularly to tracker bars as employed in mechanical piano players and the method of constructing them.

The object of the invention is to simplify the structure as well as the method of constructing and assembling such devices whereby they will not only be cheapened in construction, but will be more efficient in use, economical in manufacture, and unlikely to get out of repair.

Heretofore it has been the custom of manufacturers in constructing tracker bars, to drill partially through the support at spaced intervals, and in the undrilled portion of the support at the bottom of each drilled hole to form an oblong, rectangular orifice or vent, by driving a punch or broach through such undrilled portion. Such orifices or vents are separated one from the other by minute portions of material integral with the support. Much difficulty has been experienced through the tendency of the walls intermediate successive orifices to fracture during process of manufacture or thereafter, whereby leakage of air is permitted from one orifice to another. It frequently happens that during the punching operation, whereby the orifice or vent is formed, the entire intermediate wall between successive orifices is carried away. The fracture or breakage of one such wall destroys the usefulness of the entire device. In such constructions, the air conduits leading to the actuating mechanism are connected within the drilled openings in the support. Difficulty has been experienced in hermetically sealing such connections. A leakage at the joint of the conduit with the support permits the conduit to communicate with an adjacent conduit or an orifice other than'that pertaining to that particular conduit. This results in a different note from that indicated upon the master sheet being played, or in the omission of the playing of an indicated note.

To provide a construction in which these Specification of Letters Patent.

Patented Mar. 9, 1915.

Serial No. 739,747.

difiiculties are obviated, is one of the primary objects of the present invention.

WVith the above primary and other incidental objects in view, as will more fully appear in the specification, the invention consists of the features of construction, the parts and combinations thereof, and the mode of operation or their equivalents, as hereinafter described and set forth in the claims.

Referring to the drawings, Figure l is a perspective view of a completed tracker bar, the number of orifices or vents thereof being reduced in number. Fig. 2 is a sectional perspective view of the support or bar prior to the engagement of the conduits therewith. Fig. 3 is a perspective view of one of the conduits. Fig. 4 is a sectional perspective view of the assembled tracker bar. Fig. 5 is a transverse sectional view of a modification of the construction, employing a support stamped or otherwise formed from sheet metal. Fig. 6 is a further modification, in which the support is formed in separable halves.

Like parts are indicated by similar characters of reference throughout the several views.

This invention relates primarily to mechanical piano players, but is not limited to such apparatus, but may be employed with any pneumatically operated apparatus,

either musical or otherwise, operated by suc-,

tion or by air pressure, in which the actuating mechanism is controlled by a traveling perforated master sheet adapted to uncover the air vents or orifices in the tracker bar, in predetermined sequence.

In the drawings 1 is the support bar, the face 2 of which forms a bearing surface for the master sheet. In its rear surface, or that opposite the bearing surface 2, the supporting bar is provided with a central longitudinally disposed recess 3, on either side of which are located longitudinal grooves 4:. in which engage corresponding portions of the frame or structure to which the support bar is attached. WVhile the recess 3 and grooves 4 are desirable, these features are not essential to the invention. Formed in the bearing surface of the bar is a longitudinal slot 5, continuous throughout its length. The conduits 6, which lead to the actuating mechanism, are formed rectangular adjacent to their extremities as shown at 7. The walls of the conduits are substantially one half the thickness of the wall desired between successive vents or orifices.

The construction is such, that the combined adjacent walls of successive conduits will form intermediate the orifices a wall of the desired thickness.

The conduits 6 are assembled side by side with adjacent Walls of successive conduits in contact one with the other, and, with the rectangular ends of the conduits engaging in the longitudinal slot 5 of the support bar. In such positions the conduits 6 are united with the support bar by soldering, dipping, welding or by other suitable and convenient means. The conduits 6 are thus assembled, preferably before the bearing surface 2 of the support bar is finished. The conduits 6 extend entirely through the support bar and in the finished device terminate flush with the bearing surface 2. By assembling the conduits in the bar before the face 2 is finished, the finishing of the bearing surface insures a smooth, even joinder of the conduits and bar.

The perforated master sheet in passing over the support bar, bears directly upon the extremities of the conduits, opening and closing the orifices thereof in predetermined sequence according to the location of the perforations in the sheet. It is obvious'that the conduits 6 might be made to project beyond the support bar, whereby the master sheet would have bearing upon the ends of the conduits only.

In Fig. 5 the support bar is shown in the form of a U shaped channel 8 pressed or stamped from sheet metal. The channel 8 is provided with a longitudinal slot in which the conduits 6 are engaged as before mentioned.

In Fig. 6 the support bar has been shown as separable longitudinally coincident with the longitudinal recess or slot, as indicated at 9. The conduits 6 may be secured by clamping them between the separable halves of the support bar. The halves of the bar are adjustable to and from each other by the adjusting screws 10 adjacent to the ends of the bar.

By forming the conduits continuous to points where their extremities are directly engaged by the perforated master sheet, danger of air leakage due to imperfect joints is obviated. Further the construction described obviates much breakage and consequent loss in the manufacture of the device.

From the above description it will be apparent that there is thus provided a machine of the character described, possessing the particular features of advantage before enumerated as desirable, but which obviously is susceptible of modification in its form, proportions, detail construction and arrangement of parts withcut departing from the principle involved, or sacrificing any of its advantages.

lVhile, in order to comply with the statute, the invention has been herein described in language more or less specific as to certain structural features, it is to be understood that the invention is not limited to such specific details, but that the means and construction herein shown and described, comprise but one mode of putting the invention into effect, and the invention is therefore claimed broadly in any of its possible embodiments or modifications within the scope of the appended claims. 7

Having thus described my invention I claim: I

1. In a tracker bar for a mechanical player employing a perforated master sheet, a bar comprising a single unit having a single continuous longitudinal slot therein, a plurality of tubular members permanently secured side by side in said slot the terminal tubes of the plurality bearing upon the ends of the slots to maintain the intermediate tubes in contact one with the other.

2. In a tracker bar for a mechanical player employing a perforated master sheet, an integral continuous bar having a continuous slot longitudinally disposed therein, whereby an unslotted portion of the bar is left at each terminal thereof, a plurality of tubular members located side by side in said slot, each tubular member being in contact with the adjacent tubular members, the terminal tubular members being in contact with the opposite ends of the slot whereby the intermediate tubes are maintained in contact one with the other. 7

3. A tracker bar comprising, a collection of tubular members arranged side by side in contact one with the other, and a supporting bar having a continuous slot therein substantially equal in length to the length of the collection of tubular members into which the collection of tubular members is inserted, the contact of the intermediate members one upon the other being maintained by the engagement of the terminal members with the opposite ends of the slot.

In testimony whereof, I have hereunto set my hand this 30th day of December, 1912. FOREST H. HARTZELL. Witnesses:

ALFRED MoCnAY, Bnss CROASMUN.

Copies of this patent may be obtained for five cents eaehtby addressing the Commissioner of Patents,

Washington, D. C. 

